Revelations! Kristin Cavallari finally explained in her new book, Balancing in Heels: My Journey to Health, Happiness, and Making It All Work, why she called off her wedding to Jay Cutler the first time around: just a typical case of cold feet!

"I always go after what I want in life, with men or otherwise, and I never settle," Cavallari, 29, shares in her tome. "If something doesn't feel right, I act on it. It's just who I've always been."

After dating for a year, the MTV reality star and the Chicago Bears quarterback memorably broke up in July 2011 when they called off their first engagement. Two weeks after the split, they even returned all of their wedding gifts to friends and family.

"At that moment, something wasn't right," Cavallari writes in her book. "A few things needed to change, and I knew the only way Jay would see how serious I was, was if I ended the relationship."

The Laguna Beach alum added in her book that she was "dying inside" during that breakup period — but she and Cutler, 32, remained friends. One of these key issues at stake was that Cavallari didn't want to be a stay-at-home wife and mom. "If I stayed at home, I wouldn't be happy," the shoe designer speculates in her book. "And would probably end up resenting Jay for it."

Ultimately, what saved their relationship was couples therapy. "I credit [our therapist] for saving our relationship," Cavallari writes. "She opened up our eyes to the other person's perspective and gave us great tools for communication. . . . We still periodically see her to this day."

Cavallari has previously opened up about working through relationship issues. In a June 2015 Twitter Q&A, the Hills star shared some of her tips with fans. "COMMUNICATION! You can't assume the other knows how u are feeling," she tweeted. "Learn 2 B a good fighter (or less of one) by saying this makes ME feel..instead of YOU did this. don't be afraid 2 B vulnerable (hard 4 me!)"

She and Cutler reconciled in January 2012 and eventually tied the knot in 2013, and are now proud parents to three kids, sons Camden, 3 and Jaxon, 22 months, and daughter Saylor, 3 months.

Cavallari's book, Balancing in Heels: My Journey to Health, Happiness, and Making It All Work, will hit shelves everywhere on March 15. 

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